Types Of Operating Systems

Batch Operating System

1.1 Types of operating systems

Being known to be one of the important software in a computer, an operating system is set to the tasks of managing the memory and processes of a computer including both the hardware and software part of a computer. You can with the help of an operating system communicate with a computer without talking to it. A computer, therefore, can be declared to be useless without an operating system (Technopedia, 2018). Since the error of first computer generation, an operating system has been there despite all the evolving processes that are known. There are a number of types of operating systems which I am going to share in this chapter.

1.1.1 Batch Operating System

In this type, there is no direct interaction between the users of the operating system with the computer (Pillai, 2017). Users have to involve the services of off-line devices a good example being punch cards to be able to prepare their jobs and there after they submit them to the computer operator. There is a need for batching jobs with similar characters together and running them as a group so as to speed up the processing rates (Anderson, 2018).  It is usually the work of the operator to make sure that the jobs that are left with him by the programmers are sort into batches with respect to similar requirements. There are some disadvantages that came with Batch Systems like the absence of user job interaction, slower speed due to delayed mechanical input-output processes, and poor prioritization.

1.1.2 Time-Sharing Operating Systems

Here, users located at different locations are able to use a particular computer just at the same time. This is also referred to by many as multitasking or a logical continuation of multiprogramming. The time of the processor that is shared by many users at the same time is what is simply termed as time-sharing (Chasing, 2018). When differentiating between Time-Sharing and Batch Systems, in Time-Sharing, the main objective here is to reduce response time whereas, in Batch Systems, the main objective is to reduce processor time. Time-Sharing Operating Systems have the advantages like Quick response time, reduced CPU idle time, and there is no duplication of software. However, it is disadvantaged in terms of reliability, poor data communication, and the user’s data is not very secure in this type of Operating System (Networks, 2015).

1.1.3 Distributed Operating Systems

Time-Sharing Operating Systems

Multiple users and multiple real-time applications are served by multiple central processors in these types of operating systems. There is the distribution of jobs among the processors accordingly (chennaicisco. 2013). Various communication lines are used by the processors like the likes of high-speed buses to communicate to each other.  Distributed systems are also referred to by many people as loosely coupled systems.  This types of Operating Systems have the advantages like a high rate of data exchange through electronic mail, sharing of resources among users, the robustness of the system since the failure of one site does not affect the other, minimal delay in processing data, and the host computer is relieved a lot of burdens (Mullins, 2018).

1.1.4 Network Operating System 

This type is set to run on the server allowing the serve r to manage users, data, security, applications and many more tasks (Cisco, 2013). This type mainly came to enable sharing of resources among users over the network. There are examples of network operating systems like Linux, Unix, Mac OS, Microsoft Windows Server 2003 among others. This type has the advantages of good server managed security protocol, the stability of centralized servers, easy upgrade process, and the advantage of remote access (ComputerNetworkingNotes. 2018). Despite all these advantages, these types of Operating Systems have downfalls like high cost, decentralization, and maintaining and updating is required regularly.

1.1.5 Real-Time Operating Systems

In these types of systems, the time interval for data to be processed and the response to input is very minimal to an extend that it ends up controlling the environment. The response time is that period hat is required from the input moment and the output time. Therefore, this is to mean that in this method, there is less response time when compared to the online type. These types are used in case of rigid time required in consideration to the flow of data (Docs.ovh.com, 2018). There is a need for a real-time operating system to have the characters of fixed time constraints to avoid failure. There are as now two types of real-time operating systems namely Hard and Soft real-time systems. In hard real-time systems, there is a guarantee of on-time completion of critical tasks and there is no secondary storage meaning the data is just stored in ROM hence you can conclude that there is no virtual memory. In case of Soft real-time systems, there are minimal restrictions. Tasks are executed in terms of priority meaning that high priority tasks are executed until they are over so that the next in line task can come in (Mitchell, 2017).

Distributed Operating Systems

1.1.6 Summary of Types of Network Operating Systems

Feature	Linux	Windows	Dos	comparison
customization	Its code can be customized to the desired level.	You only have the capability to change the color, background, and fonts of the desktop.	The only option to customize it is by downloading its expansions.	Of all the three, Linux is the most customizable due to its character of being open source. Despite Dos being open source, there is no GUI which can be customized. Windows can be customized it in terms of appearance and nothing more.
Portable media connectivity.	Only a software development kit is downloaded to support connectivity.	It supports a wide range of connectivity including Bluetooth, Wi-Fi, USB among others.	No much connectivity is provided for what can be termed as fixed HDD.	Windows is the one with more connectivity, Linux is enabled by an expansion that is downloadable, and DOS is an old OS, has no support for connectivity media but you can find connectivity on those that are built on top of Windows.
Security	Linux is secure in that an administrators password is needed for any change to be made and also by being able to modify the code, you can improvise your own security measures.	There is an administrative user in Windows that has the capability to make changes and minor privileges given to other users.	No big threats come with DOS since it doesn’t support multiple users.	Linux is the most secure due to its customization character. Windows is the most insecure due to its popularity. DOS also has fewer threats due to its existence before viruses were created.
Stability	Since the code for Linux can be rewritten, it is more stable.	The version for Windows that is more unstable is Vista and it crushed after its release giving way for Windows seven	Dos is much stable due to the missing user interface.	Linux is much stable than the rest due to the absence of more software running unlike in Windows. Linux is the popular one compared to DOS. DOS takes less memory than the rest and has no GUI meaning no graphics needed.
Reliability	It can run for more periods without the need to reboot hence more reliable.	Windows has a lot of crushing and rebooting hence need for rebooting several times.	It is less reliable since it also crushes as a result of poor commands.	Out of the three, Linux is the most reliable, unlike DOS where a program that opens wrongly crushes it.
In terms of management	There is a need for you to understand programming languages to make changes for ease  management.	Due to its popularity, people find it easy to work with windows.	There is only one way to work with DOS which knows the commands. That’s to mean it is hard to manage	Among the three, windows is the easiest to manage, Linux is less easy for those who know the commands but DOS is the most complex.

1.1.7 My Recommended Network Operating System

I recommend installation of windows server 2016

Network Capabilities for Windows Server 2016

The network capabilities for Windows are complex compared to Linux. There are only two ways of setting up a network in Windows unlike in Linux where it can be done manually (Lowe, 2016). There is an option of using a Network Setup Wizard for new users and there is also a manual way used by experts which in this case is more tedious.

1.2 Business Continuity and Disaster Recovery

Business continuity is proactive measure put in place by an organization in the process of making sure that after a disaster, there is a continuation of its functions (Rouse, 2018). There is a complete planning that is set up putting in mind long-term challenges that may arise for the organization to succeed. Disaster recovery, on the other hand, is more of reactive in nature meaning are set options that an organization can take after a disaster so that it can bounce back to its normality. Disaster recovery focuses on the technological infrastructure whereas Business continuity bases on the organization as a whole unit (Plett, 2018). The similar thing about them is that they both put in mind various events that are unplanned like cyberattacks and natural disasters. They also focus on a goal of getting a business to run in a normal way.

1.2.1 Advantages of the Disaster Recovery Plan

– At the end of the exercise, the hardware and data are always protected.
– A business is more prepared for any disaster that may come by.
– Down-time is reduced and recovery for essential data is easy.
– An image of an organization is protected hence it will stand out to be a reliable company.

1.2.2 Types of backup options and devices

Unlike the past where it was hard for you to backup due to the high cost of tape drives, today there are a number of back up devices and options as you may wish (SearchStorage, 2015). A good example is CDs, DVDs, and External Hard Drives Online Storage Services among others. 

1.2.3 Backup options

There are generally three options for the backup processes namely, incremental, full, and differential.

Full Backup

Here, a full copy of all your data set is backed up. There is a lot of time taken for this process hence most organization don’t go for it. The number of tapes required is also the reason as to why it is not mostly used.

Network Operating System

Incremental Backup

They came as a way to reduce the time taken while doing a full backup. It is known to only backup the data that changes during the previous backup (Slater, 2015). This type has the disadvantage of time consuming when trying to restore and in the process, if one tape happens to be damaged or missing, there cannot be a full restoration.

Differential Backup

This type is similar to incremental in a way that at the start, there is a full backup but as the process continues, only data that has changed is backed up (Meena, 2017). This type contains all the data that has changed considering the last backup, unlike incremental backup where it only contains data that has transformed since the preceding backup. This type also has the advantage of shorter restore time compared to incremental backup.

Synthetic full backup 

This is known to be a variation of the incremental backup where by it takes data step by step unlike the original incremental where a full backup is taken and a sequence in the incremental backup (Stanek, 2018). The backup server in this type has the capability to produce a full backup. The full backup is combined with data that comes from the incremental backup to produce a full backup. It has an advantage of reduced restore time. There is also decreased time taken to backup.

Increased-forever backup 

There are disk-to-disk-to-tape systems which are used in this type of backup. A full backup of data is taken at the start just like the incremental backup. It has an advantage of data availability due to the automation of restoration process meaning you can easily figure out the kind of data that you want to restore (Mbaocha, 2012). 

The best backup type

An organization has to consider the kind of backup that is the best based on the kind of data they have and how they value data security (cloud-services, 2017). An organization before going for a certain type has to ask itself questions like;

– What type of backup is compatible with my applications?
– Considering the recovery of data, what does my service-level agreement state?
– Are the policies with respect to storing of backup tapes offsite favoring the backup type I want?

1.2.4 Different RAID options in relation to availability

There is no organization that can wish to manage two or more systems that perform a task that can be handled by one system (Guide, 2011). However, there is need to understand the organization’s use case for the success to be realized. This is also the same thing with RAID arrays and archiving. Earlier, there were only two choices for the enterprise archives which were RAID arrays and tape Silos (Subnetting, 2010). Despite Tape Silos being a cheaper way to archive a large amount of data, a lot of enterprises are going for the RAID arrays with the target of re-purposing them in the process of using them. There are currently modern disk-based archives which have the characters of data durability, rapid retrieval of data and an entry price that is more affordable. Through hardware and redundancy, the storage system availability can be achieved but data redundancy can be achieved through durability (Macken, 2016).

Real-Time Operating Systems

There are more than two hardware components that are supported by RAID arrays which include I/O paths, controllers among others which are set to service the drive failures. Six nines (99.9999) availability are achieved by RAID arrays which can put your data at a great risk if they fail www.tutorialspoint.com, 2018). RAID has an advantage in that failure of one drive brings in high chances of the other backup drive to fail.

The Modern Approach

High availability storages that are object based are used nowadays which are estimated to achieve an approximation of 99.9999999999999% or even more with an effort of ensuring perfect data preservation (Administrator. 2018). It, therefore, means that no matter the amount of objects you can store, there is only one that is readable. The way data is laid out on storage and encoded makes it easy for a durable archive to make its achievements.

2.1 Plan for the Implementation of NOS

2.1.1 Installation

Hardware Requirements

Windows Sever 2016 Minimum Hardware Requirements
Item	Windows server 2016
Processor	2.0 GHz
RAM	1GB
Disk Capacity	64GB 1204872120

2.1.2 IP addressing

10.10.10.0/24 is the class range of IP used.

Serial Number	Component	IP
1	Web server	10.10.10.2
2	DNS server	10.10.10.3
3	DHCP server	10.10.10.4
4	Core Switch	10.10.10.1
5	Firewall	10.10.10.252
6	File server	10.10.10.14
7	Users (Dynamic)	10.10.10.30-10.10.10.250
8	Printers (Static)	10.10.10.15-10.10.10.21
9	Remote support users PPT/VPN IP	10.10.10.11

Future Expansion

IP subnet

S.NO	Device	IP
2	L2 Cisco stackable Core Switch	10.10.10.10
3	Project Specific Server with different VLAN access	80

Branch connectivity

S.NO	Device	IP
1	Router (Cisco MPLS)	10.10.10.100
2	L2 Cisco stackable Core Switch	10.10.10.200
3	File server	10.10.10.253

2.1.3 Network Security Policies

Password Policy: states that it is the responsibility of individuals to take care of their system access credentials and must meet the standards and parameters of the passwords stated in the policy (De, 2015).

Patch Management: this involves testing of an administered computer system by acquiring it and installing several patches (changing code). The tasks of patch management include making sure the patches are installed correctly, determining the appropriate patches, keeping record of available patches, and documenting specific configurations necessary (SearchSecurity, 2015).

Disaster Recovery Plan

Come up with a disaster recovery team and define the roles and responsibilities of every team member. The teams will include network team, server team, and application team. It is important for the every member to be well-informed, motivated, and dedicated to handling the situation at hand. Appoint a recovery lead to who will guide other members to take action. The network team to identify and document the damage the network experienced and reestablishes network operations (Rouse, 2009). The server team will diagnose the situation and the impact the disaster has had on the server then ensures server functionalities are brought back to normal. Finally, the application team will ensure that the applications that facilitate the daily operations of the company are installed and configured for use (Coleman, 2012).

2.2 Justification of Evaluation Plan and User Feedback

The scope and requirements have to meet the future needs of the business as mentioned in the business plan. It is important to ensure that user feedback is documented to ensure continued support and enforcement of security measure to prevent any disaster from occurring (Blogspot.in, 2015). The minimum hardware requirements have been set to ensure that the company operations are smooth and that there is minimal downtime.

Summary of types of Network Operating Systems

3.1 Step by step installation and configuration of windows server 2016

Step 1: Boot the computer using windows server DVD/USB. The DVD/USB should be bootable.  Click on “Next.” You will see a screen like the one shown below.

 

Step 2: Click on “Install Now”

 

Step 3: Activate the Operating system by keying in the product key or click on “I don’t have product key” to skip the activation window as shown below

Step 4: Read and agree to the term of use by clicking on the check box “I accept the license terms” the click on “Next”

 

Step 5: Click on “custom: Install Windows only (advance)” to select your preferred version of windows server 2016.

 

Step 6: Choose your preferred version of the OS. For this case “Windows Server 2016 Standard/or/Datacenter (Desktop Experience)” was selected.

 

Step 7: Delete the existing partitions in order to set up the server a fresh.

Step 8: Create a new partition to install the operating system.

 

Step 9: Click Next and the installation process will start.

 

Wait for the installation process to finish before proceeding to the next step.

Step 10: after the installation process has finished start setting up your server for use.

 

Set Administrator password and click on “finish”

Step 11: Press control+Alt+Delete to bring up the login screen.

 

Press [CTRL-ALT-DEL] to bring up the login screen

Step 12: Login in to the server by entering the administrator password.

 

Type in the password and press enter and you are good to go.

3.1.1 Configuring Network Services

Static IPv4 and IPv6 Configuration

1. Click start, then Network. For Internet explorer, click network and sharing center on the toolbar.
2. Click Manage Network Connections in the Network and Sharing center. Right click the connection to work with under the Network Connections. Select properties.
3. Double click Internet protocol version 4 or Internet protocol version 6(TCP/IPv6) according to the type of IP address you are configuring.
4. Do the following if you are configuring IPv6 address
-Select use IPv6 Address. Type the address in the IPv6 address text box. Note: The address assigned to the computer should not be used at the any point in the network.
-Click the Tab Key. The Subnet prefix length enables the computer to communicate well over the network. A default value for the subnet prefix should be inserted on Windows Server 2008. The default value should suffice if the network does not use variable-length subnets.
5. Do the following for the IPv4 address.
-Select use IPv6 Address. Enter the address in the IPv4 Address box. Note, the address assigned to the computer should not be used at any point in the network.
-Click the Tab Key. The Subnet Prefix length enables the computer to communicate well over the network. A default value for the subnet prefix should be inserted on Windows Server 2008. The default value should suffice if the network does not use variable-length subnets.
6. Specify the default gateway if the computer requires to access other TCP/IP networks, other subnets or the internet. In the Default Gateway text box, enter the IP Address of the network default’s router.
7. Select Use Th011e Following DNS Server Addresses. In the text boxes provided enter the preferred address and an alternate DNS Server address.
8. After finishing, click Ok three times in order to save the changes made. Repeat the procedure to +42configure other IP protocols and other network adaptors.

Advantages of the Disaster Recovery Plan

Dynamic IP Addresses Configuration.

1. Click start, then Network. For Internet explorer, click network and sharing center on the toolbar.
2. Click Manage Network Connections in the Network and Sharing center. A single LAN connection is shown in the Network Connections for every network adaptor created. The single connection is created automatically. If there is no LAN connection for the installed adaptor, check the adaptor’s driver. It might have been incorrectly installed.
3. Right click the preferred connection. Select properties.
4. Double click Internet Protocol version 4 (TCP/IPv4) or Internet Protocol Version 6 (TCP/IPv6) according to the preferred connection selected in step 3. If preferred, select Obtain DNS Server Address automatically. Or select Use The Following DNS server address and enter in the text boxes provide, the alternate and preferred DNS server address.
5. You should configure an automatic alternative address if you are using IPv6 Address for the desktop computers. To do this, select Automatic Private IP address on the Alternate Configuration Tab. Select Automatic Private IP address. Click Ok. Click Close and skip the remaining steps.
6. For IPv4 Addressing with the mobile computers, it is preferred to configure the alternative address manually. To do this, select User Configured on the Alternate Configuration Tab. Enter the preferred IP Address in the text field provided. Note, the IP address given to the computer should be Private IP address and must not be used elsewhere in the network.
7. For the dynamic IPv4 addressing, Complete the alternate configuration by entering the subnet mask, DNS, default gateway and the WINS settings. Click OK twice when you have finished to save the changes.

Multiple IP Addresses and Gateways Configuration

1. Click Start, then click Network. For Internet explorer, click network and sharing center on the toolbar.
2. Click Manage Network Connections in the Network and Sharing center. Right click the connection to work with under the Network Connections. Select properties.
3. Double click Internet protocol version 4 (TCP/IP) or Internet protocol version 6(TCP/IPv6) according to the type of IP address you want to configure.
4. To open Advanced TCP/IP Settings dialog box, click Advanced.
5. Under the IP Address, click Add to pop-up the TCP/IP Address dialog box. Enter the IP address in the IP address field.  Enter the Subnet Mask I the subnet mask field for IPv4. Or the Subnet Prefix Length filed for IPv6. Then click add to return to the Advanced TCP/IP settings dialog box. Repeat this step for every IP address you may want to add.
6. Finish by clicking OK three times to close the dialog boxes and to save the changes.

DNS Resolution Configuration

1. Click Start, then click Network. For Internet explorer, click network and sharing center on the toolbar.
2. Click Manage Network Connections in the Network and Sharing center. Right click the connection to work with under the Network Connections. Select properties.
3. Double click Internet protocol version 4 (TCP/IP) or Internet protocol version 6(TCP/IPv6) according to the type of IP address you want configure.
4. If you want to specify the DNS server address for the computers using Dynamic Host Configuration Protocol (DHCP), select the DNS server Address Automatically. Else, select Use The Following DNS Server Address. Enter the primary and alternate DNS server addresses in the text fields given.
5. Finish by clicking OK three times to save the changes.

3.2 Configuration and Testing of Password Security Policy

3.2.1 Threat and Password Permission Policy

It is necessary to enforce endpoint security in order for the network admin to easily identify threats. It is important to track the IP addresses outside and inside the network and implement strong group password policy (Carpenter, 2015). The password policy ensures that all the network users met the standard requirements of the password set out such as password length and characters.

3.2.2 Network Performance and Availability

Real-time supervision of hardware and software is possible in order to define alert thresholds and automatic actions, display of network performance, data customization to collate logs, and report generation from a single console (Cisco, 2013). Analysis of how the network ensures that any abnormally is easily identified and isolated for further analysis and ensures that the network operations are not affected.

4.1 Network Monitoring Tool

Paessler PRTG

PRTG is software used to monitor network performance an operations and is commonly known for its advance capabilities of managing network infrastructure. All systems, applications, devices, and traffic on the network can be easily summarized depending on the utilization and bandwidth transmitted over the network (Carpenter, 2015).  PRTG uses technology such as WMI, HTTP requests, SQL, SNMP, SSH, and REST APIs to monitor IT infrastructure.

 4.1.1 Justification

It has a user friendly and powerful interface which will best suit the company to monitor its network effectively.

One unique PRTG feature is the capability to use a mobile app to monitor devices in the datacenter. Every sensor has a generated QR code that corresponds to the physical hardware (Pillai, 2017).

4.2 Network Monitoring against Threats

Rouse (2018), in his article brings out that it is important for the network administrator to constantly monitor all the activities running in the domain controller for in order to track and trace any anomaly on the network. Activating syslog on the network and in the data center is recommended because it makes the process of monitoring and auditing easier. Syslog process help in detecting threats and risks and alerts the network administrator to take action against the threat. In addition to syslog, other tools such net flows, IDS, and IPS are capable of detecting and trapping network threats raises and alarm for action to be taken. 

 

Figure 1: Patch Management Overview

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